Odd Networking Issue. Any ideas???

I have a small home network( desktop with shared printer) and a laptop. Not really used the network itself for ages, but tonight, the wife wanted some pictures putting on the desktop where we store all the pictures. Fired up the laptop, but the network refused to work. Got the dreaded you may not have permissions to use this network resource, on either the desktop or laptop or even the workgroup itself!!! Tried evrything I could think of to fix, net user guest was inactive for some reason, so activated it, looked in the Group policy editor, all seemed fine. NetBios still on ( I use static IPs). Still nothing at all. Nothing would see each other. Finally looked in the router settings, as the ST585 stores info on all connected PCs, and it looked very strange. Alot of MAC addresses I have never seen before, and firewall was off. Changed firewall back to standard again, and deleted all PCs from the routers memory. (Wireless security is on, with WPA-PSK security, and a password no-one would ever guess in a month of sundays!!) Laptop which is wireless, was labelled at on eth port 2, as was the desktop, which is connected to the router via Dlink Homeplugs. Suddenly, the router showed the laptop, was on wireless, when I moved it downstairs again, and networking came to life. Then all of a sudden again, the router decided the laptop was also on eth 2. Both systems could access the internet fine. Could this cause my networking woes, as does the router think I have a conflict? When the laptop was showing as wireless(which it is!!), could ping things OK. Now cant ping anything from either PC, apart from the router. Is the router just playing silly buggers, or is this a more underlying issue...Cheers for any advice

Re: Odd Networking Issue. Any ideas???

Just had another check of this, the ethernet cable for the homeplug, was actually connected to Eth03. Nothing is actually connected to ETH02. Very odd. Done a full factory reset of the router, and it appears to detect the Laptop as wireless now. Will check the network later on. Was a pain, as the router defaulted to PPPoE, with 8,34. Took me ages to sort out